/* ===================================
   CSS VARIABLES - Monochrome Swiss Design
   Design Philosophy: Minimalist, Modern, Mobile-First
   =================================== */

:root {
    /* === MONOCHROME COLOR PALETTE === */
    /* Primary Backgrounds */
    --color-white: #FFFFFF;
    --color-off-white: #F5F5F5;
    --color-light-gray: #E8E8E8;

    /* Text Colors */
    --color-black: #000000;
    --color-dark-gray: #4A4A4A;
    --color-medium-gray: #8C8C8C;

    /* Borders & Dividers */
    --color-border: #D4D4D4;
    --color-subtle-border: #ECECEC;
    --color-border-subtle: rgba(0, 0, 0, 0.08);
    --color-border-light: rgba(0, 0, 0, 0.12);

    /* Interactive & Disabled */
    --color-accent: #000000;
    --color-accent-hover: #4A4A4A;
    --color-disabled: #BDBDBD;

    /* === SEMANTIC COLOR ASSIGNMENTS === */
    /* Portfolio Hub */
    --portfolio-bg: var(--color-white);
    --portfolio-bg-secondary: var(--color-off-white);
    --portfolio-text: var(--color-black);
    --portfolio-text-muted: var(--color-medium-gray);
    --portfolio-accent: var(--color-black);
    --portfolio-border: var(--color-border);

    /* E-Commerce Shop */
    --shop-bg: var(--color-off-white);
    --shop-bg-white: var(--color-white);
    --shop-text: var(--color-black);
    --shop-text-muted: var(--color-dark-gray);
    --shop-accent: var(--color-black);
    --shop-accent-hover: var(--color-dark-gray);
    --shop-border: var(--color-border);
    --shop-primary: var(--color-black);

    /* Business Demo */
    --business-bg: var(--color-white);
    --business-bg-secondary: var(--color-off-white);
    --business-text: var(--color-black);
    --business-text-light: var(--color-dark-gray);
    --business-accent: var(--color-black);
    --business-primary: var(--color-black);
    --business-border: var(--color-border);

    /* === TYPOGRAPHY === */
    --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-heading: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;

    /* === SPACING (refined baseline grid) === */
    --space-xs: 6px;
    --space-sm: 12px;
    --space-md: 18px;
    --space-lg: 24px;
    --space-xl: 36px;
    --space-2xl: 48px;
    --space-3xl: 72px;

    /* === BORDER RADIUS (minimal) === */
    --radius-sm: 2px;
    --radius-md: 4px;
    --radius-lg: 8px;

    /* === SHADOWS (Premium polish) === */
    --shadow-xs: 0 1px 2px rgba(0, 0, 0, 0.04);
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.08);

    /* === TRANSITIONS === */
    --transition-fast: 0.15s ease;
    --transition-normal: 0.3s ease;

    /* === LAYOUT === */
    --container-max: 1200px;
    --container-narrow: 800px;

    /* Grid Columns */
    --grid-mobile-cols: 4;
    --grid-tablet-cols: 8;
    --grid-desktop-cols: 12;

    /* Grid Margins */
    --grid-mobile-margin: 16px;
    --grid-tablet-margin: 24px;
    --grid-desktop-margin: 32px;

    /* Grid Gutters */
    --grid-mobile-gutter: 16px;
    --grid-tablet-gutter: 24px;
    --grid-desktop-gutter: 24px;
}

/* === GLOBAL RESET & BASE === */
*,
*::before,
*::after {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-primary);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    margin: 0;
    padding: 0;
}

/* === UTILITY CLASSES === */

/* Spacing Utilities */
.u-mt-xs {
    margin-top: var(--space-xs);
}

.u-mt-sm {
    margin-top: var(--space-sm);
}

.u-mt-md {
    margin-top: var(--space-md);
}

.u-mt-lg {
    margin-top: var(--space-lg);
}

.u-mt-xl {
    margin-top: var(--space-xl);
}

.u-mb-xs {
    margin-bottom: var(--space-xs);
}

.u-mb-sm {
    margin-bottom: var(--space-sm);
}

.u-mb-md {
    margin-bottom: var(--space-md);
}

.u-mb-lg {
    margin-bottom: var(--space-lg);
}

.u-mb-xl {
    margin-bottom: var(--space-xl);
}

.u-pt-xs {
    padding-top: var(--space-xs);
}

.u-pt-sm {
    padding-top: var(--space-sm);
}

.u-pt-md {
    padding-top: var(--space-md);
}

.u-pt-lg {
    padding-top: var(--space-lg);
}

.u-pt-xl {
    padding-top: var(--space-xl);
}

.u-pb-xs {
    padding-bottom: var(--space-xs);
}

.u-pb-sm {
    padding-bottom: var(--space-sm);
}

.u-pb-md {
    padding-bottom: var(--space-md);
}

.u-pb-lg {
    padding-bottom: var(--space-lg);
}

.u-pb-xl {
    padding-bottom: var(--space-xl);
}

/* Text Utilities */
.u-text-center {
    text-align: center;
}

.u-text-left {
    text-align: left;
}

.u-text-right {
    text-align: right;
}

.u-text-black {
    color: var(--color-black);
}

.u-text-dark {
    color: var(--color-dark-gray);
}

.u-text-muted {
    color: var(--color-medium-gray);
}

.u-font-bold {
    font-weight: 700;
}

.u-font-semibold {
    font-weight: 600;
}

.u-font-medium {
    font-weight: 500;
}

.u-font-normal {
    font-weight: 400;
}

/* Display Utilities */
.u-hidden {
    display: none;
}

.u-block {
    display: block;
}

.u-inline-block {
    display: inline-block;
}

.u-flex {
    display: flex;
}

.u-grid {
    display: grid;
}

/* Responsive Utilities */
.u-desktop-only {
    display: none;
}

.u-mobile-only {
    display: block;
}

@media (min-width: 1024px) {
    .u-desktop-only {
        display: block;
    }

    .u-mobile-only {
        display: none;
    }
}

/* === TOAST NOTIFICATIONS === */
.toast-container {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 9999;
    display: grid;
    gap: 10px;
}

.toast {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    padding: 16px 24px;
    border-radius: 0;
    background: var(--color-black);
    color: var(--color-white);
    border: 1px solid var(--color-black);
    animation: fadeInUp 0.3s ease;
}

.toast-message {
    flex: 1;
    line-height: 1.4;
}

.toast-close {
    background: none;
    border: 1px solid currentColor;
    color: inherit;
    width: 44px;
    height: 44px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    font-size: 16px;
    line-height: 1;
    padding: 0;
}

.toast-success {
    background: var(--color-white);
    color: var(--color-black);
    border: 1px solid var(--color-border);
    box-shadow: var(--shadow-md);
}

.toast-error {
    background: var(--color-black);
    color: var(--color-white);
    border: 1px solid var(--color-black);
    box-shadow: var(--shadow-md);
}

.toast-warning {
    background: var(--color-light-gray);
    color: var(--color-black);
    border: 1px solid var(--color-dark-gray);
    box-shadow: var(--shadow-md);
}

@media (max-width: 640px) {
    .toast-container {
        left: 16px;
        right: 16px;
    }

    .toast {
        width: 100%;
    }
}

/* === ANIMATIONS === */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(10px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }

    to {
        opacity: 1;
    }
}

.animate-fade-in {
    animation: fadeIn 0.6s ease forwards;
}

/* === BREAKPOINTS === */
/* Mobile: 0-639px */
/* Tablet: 640-1023px */
/* Desktop: 1024px+ */

@media (min-width: 640px) {
    :root {
        --grid-cols: var(--grid-tablet-cols);
        --grid-margin: var(--grid-tablet-margin);
        --grid-gutter: var(--grid-tablet-gutter);
    }
}

@media (min-width: 1024px) {
    :root {
        --grid-cols: var(--grid-desktop-cols);
        --grid-margin: var(--grid-desktop-margin);
        --grid-gutter: var(--grid-desktop-gutter);
    }
}